It is a good idea to save your searches in some form to be able to go back and continue working with them later. For instance, you take a screen shot or copy your search strings from the databases. You can also create an account and save your searches and interesting articles directly in the database. This is how you do it in MLA International Bibliography:
Click "Search history"
Select the search you wish to save
Click "Save searches/Alerts"
Name your search, click "Save" and "Continue"
You can now find your saves searches under "Folder"